Motorized roller blind

Abstract

A motorized roller blind comprises a housing in which at least one roller member is rotatably mounted, and a strip of material forming the blind member which is fixed to the roller member at one end and to a pull bar at the other end. Actuating means comprise first and second links each having a first end pivotally fixed to the pull bar in the vicinity of a respective end thereof, and a second end pivotally fixed to a coupling member which is itself fixed to a respective end of a rack drive member adapted to be displaced by a drive pinion drive by a motor.

We claim: 
     
       1. A motorised roller blind comprising an elongate housing, at least one roller member in the housing, at least one strip of material having a first end fixed to the roller member and a second end, a pull bar fixed to said second end of said at least one strip, and actuating means comprising first and second links of a length equal to approximately half the length of the housing, each link having a first end pivotally connected at a fixed point to the pull bar in the vicinity of a respective end thereof and a second end, a respective coupling member to which the second end of an associated said link is pivotally connected, a respective rack drive member having an end to which a respective said coupling member is connected, each rack drive member being of a length equal to approximately half the length of the housing, a drive pinion mounted rotatably in the housing substantially at an equal distance from the ends of the housing, with said drive members being disposed on respective sides of and engaging with said drive pinion, and a motor adapted to drive the drive pinion. 
     
     
       2. A blind as set forth in claim 1 wherein said drive members are cable racks and further including sliding guide means operable to hold said cable racks in engagement with said drive pinion. 
     
     
       3. A blind as set forth in claim 1 and further including travel limiting abutments disposed in the housing facing said ends of the respective drive members. 
     
     
       4. A blind as set forth in claim 1 and further including travel limiting abutment means on said pull bar. 
     
     
       5. A blind as set forth in claim 1 comprising first and second said roller members, and first and second said strips which are each fixed to a respective said roller member, and a common curved pull bar associated with said first and second strips.